Coupling



Nov. 9, 1943. F. M. CRAY'VI'ON 2,333,986

COUPLING Original Filed March 50, 1940 2 Sheets-Sheet 1 1943- F. M.CRAYTON 2,333,986

COUPLING Original Filed March 30, 1940 2 Sheets-Sheet ,2

M a a 43mm Patented Nov. 9, 1943 STATES PATENT OFFICE 2,333,986

COUPLING 7 n Foster n. Crayton, Philadelphimla. OriginalapplicationMarch 30, 1940, Serial No;

326,949. Divided and this, application August ,30, 1941, Serial No.408,953 g 2 Claims.

My invention relates to the art of work-holders for machine tools. v

This application is a division of 'my copending application Serial No.326,949, filed March 30, 1940, for coupling. l r

One purpose of my invention is to provide a coupling for clamping boltsused-in work-holders, whereby the effective length of the holding boltis extended, the coupling having threaded engagement with one bolt andtransverse slot and bolt head engagement with the other bolt.

A further purpose is to provide a coupling for joining two bolts havingthreadedengagement .with one bolt and transversehead and slot engagementwith the second bolt and having the second bolt locked in transverseposition within the coupling slot by engagement between the end of thefirst bolt and. the head of the second bolt.

A further purpose isto provide a base for a packing piece, commonlyknown as a hell block, for work clamping use, having a nut for'boltengagement at the upper end of the base, laterally and downwardlyextended at its lower end, and with a transverse slot in the bottom.

A further purpose is to provide a combined couplingand hell block'basesuited to receive a bolt at one end and laterally extended andtransversely slotted at the other end to receive the T-head of a secondbolt, the head ofthe second bolt being recessed to receive the end ofthe first bolt for centering and clamping purposes. I

A further purpose is to provide a special slotted block and nut forsupplemental use in support of work upon a table. 1

Further purposes will appear in the specification and in the claims.

Figures 1 and 4 are perspective views taken from different positionsshowing a bolt usedby Figure 2 is a side elevation, partly sectioned, ofthe bolt of Figure 1. r i

Figure 3 is a section upon line 3-3 of Figure 2.

Figure 5 is a side elevation, partly sectioned, showing a work clamp,bolt and hell block in position clamping work on a bed.

Figures 6 and 7 are perspectives from different positions of a combinedcoupling and hell block base. t

Figure 8 is a broken side elevation showing clamping structure forholding work.

Figure 9 is a section of Figure 8 taken upon line 9-9. I

Figure 10 is a perspective of the fitting seen in Figures 8 and 9.

Figure 11 is a perspective view of a nut adapted to slidewithin the slotof a machine tool table or bed.

Figures 12 and 13 are longitudinal, transverse vertical centralsections, respectively, through the nut of Figure 11. t

Figure 14 is an end view of Figure 11. In the drawings similar numeralsillustrate like parts.

In clamping work on'the beds or tables of machine tools provided withslots, as in a planer bed, it has been customary for a great many yearsto use T-headed bolts within the slots, to pass the bolts throughclamps, plates or other transverse holding devices, resting one end ofthe clamp against the work and to rest the other end of the clamp uponpacking pieces acting as fulcrum blocks and commonly known as hell.order tomeet this need I provide couplings be- "tween shorter bolts sothat therange of bolt lengths which much he carried may be reduced.

,My present invention relates not only to the couplings used, but to abase for a built up fulcrum block or hell block, to a T-nut and to afitting, all concerned with the holding of work on beds or tables.

, I show at 15 a fragmentary machine tool bed or table having a slot [6(Figures 2 and 3) into which fits the T-head ll of a T-bolt l8. As iscustomary the sides I9 of the bolthead are an easy transverse fit in thelower (wide) part of the slot, and the stem 2| of the T-bolt iselongated in the direction of the length of the slot and forms an easyfit between the overhanging flanges 22 and 23 of the slot.

There has been difliculty in moving T-bolts lengthwise of such machinetool bed or table slots because chips and other obstructions fallinginto the slots become wedged between the heads .ll of the bolts and theside walls 24 and 25 of the lower (wider) parts of the slots. Thisoccurs of course in either direction of movement of this interference ofchips, etc., with the movement of the belt.

I concave both ends of the T-head at 26, concaving also the stem of theT as at 21. Whichever the direction of movement of the T-head along thelength of the slot, this therefore provides horns 28 near the sides ofthe slot, with concave and preferably sloping surfaces adjacent, guidingthe chips toward the lateral center line. This frees that part of theslot under the flanges from chip engagement, thus avoiding having thechips wedge between the outer limits of the bolt heads and the adjacentlower slot side walls 24 and 25.

In addition to concaving the front and rear faces of the cross of the Tand the stem of the T, I slope the central portion of the bar and stemof the T adjacent the T-head upwardly and inwardly from the bottom ofthe bolt'face to the top of the stem of the T at .29, as shown best inFigure 2. The chips which have :beencentered by the concavity of the endof the bolt T-head will be guided upwardly and hence outwardly of theslots by the slope.

I prefer ;to make the. concavities of the .endsof the bolt head curvedin transverse section,.though other transverse concavity contours thanof a curve would be of benefit to attainzmy purpose.

Not only does the curved en'dcdrawichipstoithe center to the bestadvantage,- but, :in :end: swaging rod stock into the'headduringmanufacture, the

face of the die which shapes the curvature guides and diverts theflowing metal to fill out-the horns at the ends of the curves. s,

The bottom of the bolt under the head is recessed at 35 so that, ashereinlater indicated, this recess may receive the threaded Send of.a-secjond bolt for-the purpose of :alining the bolts andmigidly holdingthem together.

When it ;is desired to use two OfLlllY-lbOltStO- gether a coupling 31 isused; 'whichcomprises a nut 32 at one end threaded at 33, adapted tore-.ceive the thread of onezofmy bolt-sand a transversely slotted terminal34 atthe" opposite end,

adapted to receive the T-head of a second of my bolts. Theslo-ttedterminal is comparable in the slot with a portion of the lengthof a machine tool slot, having the same characteristics for its shorterlength as those of the machine tool slot, including overhanging slotflanges; EWldliSlOt space largely beneath the flanges. and a narrowerspace between the flanges for the stem-of the second bolt head. Theends'of theslotwalls are concaved at Elto correspond generally' with theconcavity at --25 in the T-headends.

When the threaded end of one bolt is passed within the thread ofsuch acoupling, their -'head of the second body is passed within the:fragmentary transverse slot oi theterminal :of the coupling, as shownin Figure 5. Part of the length of the threads of the lower:b'olt'andthe nut of the coupling may be iusediforradjustment of theheight-cf the combined unit. bolts and coupling, but'more usuallythenutof-thecouplin'g will be screwed down-onthe-sthread of theilowei' bolt tosuch an'extent that the end' 35 of 'the threaded part of the :lower boltwill flt into'the recess 39 within thehead of .the flipper-bolt. 'It

may thus merely prevent lateral movement of the head of the second .boltin the slot or the parts may be threaded tightly against-one :an

other so as quite rig-idly to hold athe-two bolt and clamptogether-inalinedyposition.

In operation, the T-head of the bolt .when moved in the-slot ineither-direction :draws the chips toward the lateral center ime of'ithelslot and, because of the upward slope, guides ithem upwardlyandoutwardlyupontheitop offiaisloping ,surface 36, on theupwardly directed:faceiof-fthe washer 36 and tightens the fitting bolt l8 having itsT-head within "a slot at Ali" on; This fitting may be T-stem and thusagainst the body of the bolt at 31 and ed to one side or other of theslot.

When the coupling is used, the lower bolt, whose head travels in the bedslot, fits into the thread in the nut end of the coupling and the T-endof the upper bolt is fitted transversely into the slot in the upper endof the coupling above the lower bolt. The coupling is threaded upon thelower bolt until the upper end of the lower bolt fits tightly within therecess 30 in the head of the upper bolt. The composite bolt thus formedis then used as if it were a single bolt length.

When the coupling is intended to be used as theba'se or bottom of thehell block, the faces 38 and 39"are roughened to assist in preventing.bleof other uses, when transversely .apertured. This structure is seenat ill in Figures ,8, 9

and 10 where :the coupling used as a fitting is provided with the .nut32at one end'which appears in Figures;8, 9 and 10 and with the transverseslot atthe other'end. However, the intermediate section 4i! has beenlengthened axially of the-nut to form an-intermediate block portionlarge enough to permit aperture at 4! .for the passage -;of -a bolt &2,smaller-in diameter than bolt l-B, transversely-of the-lengthzof thefitting.

The sides of the fitting are flattened at 43 adjacent the opening ofaperture 4! to permit clarnping of the fitting; against a table 4d atright-angles .tothe main-table l 5"-(Fig,ure 8) upon which work 451 tobe clamped.v Anysuitablespacing washer orblock 46 is inserted so thatathebolt 18 will engage the workconveniently. Nut lfi rests/on so thatany can beusedto-engage the work or to engage any suitable upportingmechanism which engages .thework I The structure of Figures 8, 9 and 10also is provided with'roughened surfaces :38 and 3fl'so that it can act'as a :hell block and with threads 33'; 1

The fitting of Figures .8, f9 and '10. affords a supplemental anchorageavailable beyond the table upon which the work Tests for the purpose oftightening or-supporting the work thereused .in other ways than thesingle illustration of its application whichhas been given.

This fitting gives an additional ofi'standing support for the-work on ashape1','for example,

provided with two tables where the work extends :beyond the one table;

InFigures 11, 12,13 and 14 a T-nut is provided corresponding generallywith the T-h'eadof the bolts *displayed but ,havinga threaded aperturein the position corresponding generally to the shank of the =:bolt r-inthe other forms. The nut is intended to be .used' to :re'ceive' a boltfrom above for clamping purposes." Since the stem of the nut does notcome up above the level of the table, additional T=nuts of thischaracter can be located in the slots ready for transfer to la point-ofpossible-use without presenting the projection problem which would beoffered by a bolt similarly placed. Besides this, any desired length ofbolt, or more usually stud, on account of its longer possibility of easyadjustment, can then be used from above, whereas the length of boltrequired might not be capable of determination at the time when the boltwould have to be selected if a bolt were to be used instead.

It will be evident that the characteristics of the T-headed bolt and theT-nut are very closely similar. Both are fittings and both are devicesby which connection may be made from slotguided members which areaccessible from above the bed, the bolt directly by the bolt shank andthe nut by the stud or bolt engaging its socket.

The character of the front and rear facing concavity is not so importantas the fact that it is concave and that it does in its final resultcollect and guide the chips so as to facilitate their removal from theslot.

The bolt and nut both are T-sections, the front and rear facings of theTs performing the same functions in relation to the slot and to thechips within the slot.

The T-nut ll of Figures 11-14 has in general the characteristics of theT-head of the bolt in that it fits easily into the wide part of the slotand has the distinctive characteristics of the T-head of the bolt. Itssides l9 are easy transverse fits in the lower (wide) part 20 of theslot and the stem 2| of the T-nut is elongated in the direction of thelength of the slot and forms an easy fit between the overhanging flanges22 and 23 of a slot. The ends of the T-nut are concaved at 26' and thestem of the T-nut is concaved at. 21' and at the upper portion 29' nearthe top 41 of the stem. It provides horns 28' and is sloped at the endsupwardly and inwardly toward the axis of its thread 48 to guide thechips outwardly from the slot.

It will be seen that the T-nut and a stud can be used together for thesame purpose and in the same way as a bolt would be used but that theT-nut has a further advantage of being capable of use as a socketmovable along the length of the slot and into which a stud or bolt canbe put to build down from the work, as distinguished from building upfrom the slot in order to obtain a clamping efiect.

In View of my invention and disclosure variations and modifications tomeet individual whim or particular need will doubtless become evident toothers skilled in the art, to obtain all or part of the benefits of myinvention without copying the structure shown, and I, therefore, claimall such in so far as they fall within the reasonable spirit and scopeof my invention.

Having thus described my invention what I claim as new and desire tosecure by Letters Patent is:

1. A fitting adapted for use in holding work, comprising a body having anut at one end of the body threaded to receive a bolt, a T-slotted faceat the opposite end of the body transverse to the axis of the nut threadadapted to receive a T-bolt, a passage at an intermediate part of thebody transverse to the axis of the thread in the nut and a clamping boltin the passage an bolted to the fitting.

2. A fitting for clamping work, comprising a body having a nut providedwith a threaded opening at one end, a slot for the T-head of a bolt atthe opposite end of the fitting,.thelength of the slot being transverseto the axis of the thread, and a passage through the fitting between theslot and nut and parallel to the length of the slot, one face of thefitting adjacent the opening being flat.

FOSTER M. CRAYTON.

